Dad and mum separated about two years ago. I took it in turns living with them three months at a time. Now was dad’s turn however I’d recently turned seventeen so when I become eighteen I can decide to live where I want then. Anyway I loved them both so I didn’t mind moving between them.
Dad was dating this lady called Billie. She was a kind lady, early forties, short brown hair, medium build, small boobs with a plump butt. She has recently moved in with him and we got along fine.
This evening it was particularly hot and I was trying to sleep. I had been horny earlier but wasn’t in the mood to jerk off even though I was hard. As I lay in bed I needed to pee so I got up and walked down the hall. As I neared dad’s room I saw the door was slightly open and as I was outside I heard dad say “Come on Billie just a handjob”. I stopped walking and listened as Billie said “But I’m tired John”. I smiled and thought dad’s out of luck however I heard a kissing noise then she said “Ok then but just a quick wank”.
As I started to move away I looked through the gap in the door and realised I could see their bed reflected in the large mirror on the wardrobe door. There was Billie sitting up wearing a yellow t-shirt and pyjama bottoms while I then saw dad lifting his bum to pull his boxers down. As he did I saw his dick spring upwards and I must admit I was envious. It was at least two inches longer then mine and thicker.
Billie then wrapped her hand around his shaft and began to slowly pull up and down. As I was watching I felt my dick harden. Why was I getting aroused? This was my dad and his girlfriend. However I couldn’t drag myself away from watching them. Billie’s hand was sliding right over dad’s tip then all the way down his shaft. As she sped up dad let out a moan and his left leg shook a little.
Then I realised my hand had slid into my pyjama shorts and I was stroking my erection while watching them. Billie rubbed her palm over dad’s tip which he seemed to enjoy and she also blew on his dick which looked so sexy. Dad’s big balls were wobbling around and as she jerked him off even faster I began jerking off in my shorts. Dad moaned again and as I felt surges of pleasure shooting through my body dad groaned loudly and white come spurted out of his dick and went all over his stomach and Billie’s hand.
I was still jerking off furiously in my shorts as Billie wiped the come off of dad and her hand then she kissed him softly on the lips and turned out the light. At that moment my balls tightened and I grabbed the door frame and tried not to moan as a shaking orgasm rippled through my body and I came hard inside my pyjama shorts. Breathless I kept hold of the frame until I stopped shaking then I walked to the bathroom and cleaned myself up before peeing.
Back in my bedroom I changed my shorts and layed on the bed. I was still questioning why I was turned on by seeing dad jerked off however after coming I was now tired so I soon fell asleep.